A conventional card socket includes a card-receiving space for receiving a card such as a memory or SD card, and a detection switch to detect the presence or insertion of the card. Such a detection switch comprises contact members responsive to insertion of the card into the card-receiving space.
FIG. 14 shows a conventional card socket for such cards. As shown, a card 101 is inserted in a card-receiving space 102 of a socket housing 100, which has first, second and third contact pieces 103, 104 and 105 mounted at one longitudinal side of the housing. First and third contact pieces 103 and 105 are adapted to be deflected during insertion of card 101. Second and third contact pieces 104 and 105 constitute a first switch used for detecting the presence of a card, for example, and first and second contact pieces 103 and 104 constitute a second switch used for a second function such as write protect. In this second function, card 101 includes a movable piece 106 at one longitudinal side thereof, and the deflection of first contact piece 103 of the write protect detection switch is controlled due to the position of movable piece 106 on card 101.
Another example of a detection switch is shown in Japan Patent Laid Open No. 11-97110 and includes a contact member responsive to insertion of a card for moving in a direction parallel to the thickness of the card until it contacts a mating switch contact. Still another example of a detection switch includes a contact member responsive to the insertion of a card by wiping the mating switch contact (see Japan Patent No. 2973402).
The contact members of a detection switch are likely to collect particles of foreign substance or to have oxide coating formed thereon, thus contributing to unstable switching conditions—particularly in a detection switch that does not include wiping action such as that shown in the conventional switch of FIG. 11.
Furthermore, a conventional detection switch uses contact members of different shapes and sizes which require multiple stamping dies and multiple parts to make up a detection switch. This contributes to the overall relatively high manufacturing, assembly and inventory costs and does not allow for the effective reduction of costs for sockets equipped with switches. For example, the detection switch of FIG. 11 uses three different kinds of contact members, and another conventional detection switch uses two different kinds of contact members. Two detection switches if combined, need to use three different kinds of contact members. This type of design is not necessarily cost effective or simple.